animation.py

#note, this program currently only works for three bodies. I will eventually work to generalize this to n bodies

#importing dependencies
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.animation as an
from matplotlib.animation import FuncAnimation

#crate position arrays

bigray = []

t = []
x1 = []
x2 = []
x3 = []

y1 = []
y2 = []
y3 = []

z1 = []
z2 = []
z3 = []

bsize = 250 #size of box

with open("body_cords.dat","r") as data: #open the dat file generated by c++ 
	for line in data: #maps the data file to the array bigray 
		raw = [item.strip() for item in line.split(' ')]	
		bigray.append(raw)
	
slices = len(bigray)

for line in range(slices): #splits the big array into smaller arrays for the x,y,z of each body
	t.append(bigray[line][0])

	x1.append(bigray[line][1])
	y1.append(bigray[line][2])
	z1.append(bigray[line][3])

	x2.append(bigray[line][4])
	y2.append(bigray[line][5])
	z2.append(bigray[line][6])

	x3.append(bigray[line][7])
	y3.append(bigray[line][8])
	z3.append(bigray[line][9])

def update(i): #updates the position of the bodies on scatter plot(s) (it is currently putting all the frames on top of each other) 
	ax.scatter(float(x1[i]),float(y1[i]),float(z1[i]),c='r')
	ax.scatter(float(x2[i]),float(y2[i]),float(z2[i]),c='b')
	ax.scatter(float(x3[i]),float(y3[i]),float(z3[i]),c='g')
	return ax

#sets up the plot
fig = plt.figure()
ax = plt.axes(projection='3d')
anim = FuncAnimation(fig, update, interval=1) 

plt.show()